– Er. Sailesh Adhikari
Lean manufacturing is a modern culture of a manufacturing practice which includes continuous efforts to exclude a waste or any action that put away resources without adding any value to the product. These wastes can be in the design of the product, any production process, and supply chain practice and after-sales services. The concept of lean manufacturing was first introduced and established by the Toyota executive Taiichi Ohno, after WWII restoration period in Japan. Later on, James P. Womack and Daniel T. Jones promote it in their 1996 book ‘Lean Thinking’ and now, it is the cultural practice of most of the big and middle-class industries throughout the world. The primary idea behind lean manufacturing is to take full advantage of resource mobilization by decreasing waste, thereby realizing manufacturing superiority through the process improvising at same available resources but with changed worked practice and the economic quantity of the resources. 5S is an established manufacturing practice, which is termed as the foundation of a lean-transformed organization. 5S encourages sequence of actions for reducing wastes that adds to nonconformities, faults, and accidents in manufacturing practice. A simple definition of the 5S practices are described with their Japanese name below:
- Seiri (Sort): Identity, separate the necessary, occasionally used, and unnecessary items.
- Seiton (Set in Order): Arrange necessary and occasionally used items into clear designated storage positions.
- Seiso (Shine): Thoroughly cleans the workplace and equipment. Cleaning is an inspection.
- Seiketsu (Standardize): Visual aids, 5S manuals, 5S audits. Standardize 1-3S.
- Shitsuke (Sustain): Practice 5S to the point where it is a natural part of your work.
To support the idea of lean manufacturing and control manufacturing process through a lean transformation, James Womack, and Daniel Jones recognized a 5-step assumption in the manufacturing process completely in their book, Lean Thinking. These five steps characterize a continuous series of development and performance as the basis for the effective application of lean in the organization. The five steps describe in his book are;
- Specify value: Recognize the value of a particular product from the buyer’s viewpoint. Value can only be well defined by the definitive customer though the producer manufactures it.
- Identify the value stream: Recognizing the total value stream for the individual product will explain three types of actions viz. the steps which create value, the steps that do not add any value but are mandatory with current methods and production machine and the steps those are nonvalue adding which can be excluded.
- Create flow: Formerly, when the value has been accurately quantified and the value stream for a particular product is completely recorded, we can redesign the production flow rearranging working elements in a continuous flow with nominal logjams so that no any further rework or stoppages is required in a lean transformation.
- Establish pull: After eliminating extravagant steps and continuous process flow has been established, it is necessary to determine the ability to deliver accordingly to customer demands. This will reduce inventory and cost associated with it. Letting consumers pull a product through the process is the manufacture’s capability to be approachable with the consumer’s needs.
- Seek perfection: As the company is successful to implement four values explained earlier, the next steps of process perfection are achievable and the company tends to perfect the methods and save economic by reducing waste of resources and time.
As we talked that lean manufacturing is the practice of reducing waste, then we should be aware of the fact; what is the waste in given process, what are the different waste in given process and how we can define and determine the waste? Lean manufacturing explains seven deadly wastes of production which are the non value-adding events or processes and activities that impede productivity of the process and reduced revenue of a company. They are:
- Waiting: Time spent waiting on something, or someone, to complete a task increase the cost. The process should be designed in such a way so that flow is continuous, and there are minimal buffers between different successive steps in the production process.
- Motion: The redundant motion of the worker that does not add value to the product or service also increase cost. The process should ensure that work areas are sensibly structured to significantly reduce excessive worker motion.
- Over processing: Over processing assign more energy or activity than it is needed to produce a product. Lean transformation suggests for best possible simplifications to the manufacturing process to significantly decrease processing time.
- Inventories and queues: Additional or just-in-case inventory can consequence in an increase of cost and sometimes loss or a waste of the resources and capitals and may cause either storage of some part and excess of some. Lean transformation aims for just-in-time inventory that subsequently decreases idle time related with any inventory problems.
- Transportation: Redundant movement of goods in processing creates higher chances of damages or delays with higher transit and also more resources and expenditure. Effective planning is necessary to ensure minimum waste in transportation.
- Overproduction: Making more parts or information than it is required is other types of waste in an organization that requires extra cost and effort. Lean transformation establishes a standard pacing material flow through the production process to match consumer demand.
- Fixing defects and mistakes: Overall time and cost spent in refurbishing or reworking on the product are another waste. The cost of fixing defects or mistakes is a lot cheaper in terms of resource mobilization if it is addressed as soon as they are found.
After understanding the lean concept, it is most important to practice it as organizational culture. Before we implement lean in the floor, we should be clear about the fact that, it is teamwork and every individual has an important role in practicing lean effectively
In actual practice of lean in the floor, there are different arenas we should consider properly. On top of all, when your company is trying lean techniques at first you need to get lean knowledge into your company, either by hiring experts or by hiring outside experts as consultants. This approach is essential as education without application is so often a waste for all. The next thing is to rely on information based on data. Before making any decision, be sure to base on actual information from your own organization and to get a real view of your company the best source is data analysis of the past. Real-time data tracking is the best source to observe the position. In order to make a strategic Lean approach work in your organization, process operators have to work in process related teams, rather than their current functional ones because in lean implementation, teams need to become truly self-directed, allowing problems to pick the people required to solve them from within the teams rather than management picking the problems and assigning them to people to solve. Another basic practice of the lean manufacturing is the team leaders are responsible for creating awareness to the members and employee and they should ensure that all members of staff are correctly coached. This avoids conflict and delivers a management group that can facilitate change with the teams working for them and so remove waste efficiently.
One of the key lean tools is that of “Value Stream Mapping”. This tool, when used correctly, enables the organization to create a map of both value and waste in a given process. This map can then be used to understand the waste and its causes before moving on to remove it so that value flows without interruption of waste. In next state, it is required to use Kaizen workshops to teach and make rapid changes. Be sure to employ talented and experienced facilitator who has a deep understanding of lean tools and philosophy but keep training focused on a specific problem. In value mapping, it is also necessary to organize around value streams to implement lean with perfect design. In most organizations, management is organized by process or function. In other words, managers own certain steps in a process but nobody is responsible for the entire value stream. In the second edition of the Lean Thinking, the authors recommend a matrix organization where there are still heads of departments but also value stream managers.
The way to get feedback for further steps it is necessary to develop two-way communication channels for everyone. This will aid in getting support through the involvement of people at various level by sharing their ideas to build synergy to move positively ahead in the lean journey. And, be sure of the fact that, if a company looks at Lean transformation as a “nice to do” in spare time or as a voluntary activity, it will simply not happen. It needs to be mandatory and people need to be given the space to think about improvements they can make. A crisis may prompt a lean movement, but may not be enough to turn a company around. Once the crisis has passed it can be all too tempting to go back to business as usual.
For the successful implementation of the lean, it is necessary to show tolerant towards mistakes committed in a lean environment with a supportive and learning attitude by the team leaders. In addition, it requires patience with progress as this will be the key to getting results and try to create a blame-free supportive environment. As a team, you should have the courage to take risks at crucial stages to push things and resources to meet the plan and achieve results.
Lean is a continuous improvement practice and there is always a point to focus on for improvements. It’s a long journey to any organization that requires passion and commitments. Every time when you finished with one level of improvements, the next level is your target. The concept of six-sigma is following after lean manufacturing. The aim of lean manufacturing is to build a culture of continuous improvement for sustainability and it goes on for the long run.